Electrochemical behavior of lead alloys in sulfuric and phosphoric acid electrolyte

The electrochemical behavior of lead, lead-calcium-tin-aluminum and lead-calcium-tin-aluminium-bismuth alloy electrode has been studied in the electrolyte of sulfuric, phosphoric and mixed acid electrolyte. The electrochemical measurements were performed using a cyclic voltammetry technique (CV) with three-electrode system. The results demonstrated that bismuth(III) doped in the lead electrode can increase electrical capacity. The oxidation peak potential of lead alloy electrode in phosphoric acid shifted to the positive compared to that in sulfuric acid. The formation of PbHPO ₄ in phosphoric acid and its passivation are responsible for the positive shift of the oxidation.